使用引用初始化对象而不访问非默认构造函数

Let's suppose I have an interface named "Controller". Several classes implement this interface and I don't know these classes (e.g. the class names are located in an xml-file). Now for this Controller-implementing classes to work they have to get some references to other objects (maybe data objects). And this is my question, namely what is the best way to initialize such objects (the Controller ones)?Let's suppose I have an interface named "Contro